US20120232400A1 - Intravascular Ultrasonic Catheter Arrangements - Google Patents
Intravascular Ultrasonic Catheter Arrangements Download PDFInfo
- Publication number
- US20120232400A1 US20120232400A1 US13/401,574 US201213401574A US2012232400A1 US 20120232400 A1 US20120232400 A1 US 20120232400A1 US 201213401574 A US201213401574 A US 201213401574A US 2012232400 A1 US2012232400 A1 US 2012232400A1
- Authority
- US
- United States
- Prior art keywords
- transducer
- elements
- transducer elements
- transducer array
- array
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 239000000463 material Substances 0.000 claims abstract description 35
- 239000000919 ceramic Substances 0.000 claims abstract description 26
- 238000003384 imaging method Methods 0.000 claims abstract 4
- 238000003780 insertion Methods 0.000 claims abstract 3
- 230000037431 insertion Effects 0.000 claims abstract 3
- 210000005166 vasculature Anatomy 0.000 claims abstract 3
- 239000000758 substrate Substances 0.000 claims description 21
- ZBSCCQXBYNSKPV-UHFFFAOYSA-N oxolead;oxomagnesium;2,4,5-trioxa-1$l^{5},3$l^{5}-diniobabicyclo[1.1.1]pentane 1,3-dioxide Chemical compound [Mg]=O.[Pb]=O.[Pb]=O.[Pb]=O.O1[Nb]2(=O)O[Nb]1(=O)O2 ZBSCCQXBYNSKPV-UHFFFAOYSA-N 0.000 claims description 10
- 238000000034 method Methods 0.000 abstract description 27
- 239000004642 Polyimide Substances 0.000 description 24
- 229920001721 polyimide Polymers 0.000 description 24
- 238000004519 manufacturing process Methods 0.000 description 19
- 230000008569 process Effects 0.000 description 15
- HFGPZNIAWCZYJU-UHFFFAOYSA-N lead zirconate titanate Chemical class [O-2].[O-2].[O-2].[O-2].[O-2].[Ti+4].[Zr+4].[Pb+2] HFGPZNIAWCZYJU-UHFFFAOYSA-N 0.000 description 14
- 229910052451 lead zirconate titanate Inorganic materials 0.000 description 13
- 229920002120 photoresistant polymer Polymers 0.000 description 9
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 8
- 229910052802 copper Inorganic materials 0.000 description 8
- 239000010949 copper Substances 0.000 description 8
- 239000000853 adhesive Substances 0.000 description 6
- 230000001070 adhesive effect Effects 0.000 description 6
- 230000008901 benefit Effects 0.000 description 5
- 230000008878 coupling Effects 0.000 description 5
- 238000010168 coupling process Methods 0.000 description 5
- 238000005859 coupling reaction Methods 0.000 description 5
- 238000000608 laser ablation Methods 0.000 description 5
- 238000003491 array Methods 0.000 description 4
- 238000002679 ablation Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 239000004593 Epoxy Substances 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 229920002457 flexible plastic Polymers 0.000 description 2
- 238000001465 metallisation Methods 0.000 description 2
- 238000007747 plating Methods 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 125000006850 spacer group Chemical group 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 239000006091 Macor Substances 0.000 description 1
- 239000004952 Polyamide Substances 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 238000003486 chemical etching Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 229910003460 diamond Inorganic materials 0.000 description 1
- 239000010432 diamond Substances 0.000 description 1
- 239000002305 electric material Substances 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- GPYPVKIFOKLUGD-UHFFFAOYSA-N gold indium Chemical compound [In].[Au] GPYPVKIFOKLUGD-UHFFFAOYSA-N 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 238000002608 intravascular ultrasound Methods 0.000 description 1
- 238000010884 ion-beam technique Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000003801 milling Methods 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 238000000206 photolithography Methods 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 229920002647 polyamide Polymers 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 229910000679 solder Inorganic materials 0.000 description 1
- 238000009987 spinning Methods 0.000 description 1
- 238000004544 sputter deposition Methods 0.000 description 1
- 230000026683 transduction Effects 0.000 description 1
- 238000010361 transduction Methods 0.000 description 1
- 238000002604 ultrasonography Methods 0.000 description 1
- 238000001771 vacuum deposition Methods 0.000 description 1
- 230000003313 weakening effect Effects 0.000 description 1
Images
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
- A61B8/12—Diagnosis using ultrasonic, sonic or infrasonic waves in body cavities or body tracts, e.g. by using catheters
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
- A61B8/44—Constructional features of the ultrasonic, sonic or infrasonic diagnostic device
- A61B8/4483—Constructional features of the ultrasonic, sonic or infrasonic diagnostic device characterised by features of the ultrasound transducer
- A61B8/4488—Constructional features of the ultrasonic, sonic or infrasonic diagnostic device characterised by features of the ultrasound transducer the transducer being a phased array
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
- B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
- B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
- B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
- B06B1/06—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
- B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
- B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
- B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
- B06B1/06—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction
- B06B1/0607—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using multiple elements
- B06B1/0622—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using multiple elements on one surface
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
- G01S15/88—Sonar systems specially adapted for specific applications
- G01S15/89—Sonar systems specially adapted for specific applications for mapping or imaging
- G01S15/8906—Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques
- G01S15/8909—Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques using a static transducer configuration
- G01S15/8915—Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques using a static transducer configuration using a transducer array
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
- A61B8/44—Constructional features of the ultrasonic, sonic or infrasonic diagnostic device
- A61B8/4444—Constructional features of the ultrasonic, sonic or infrasonic diagnostic device related to the probe
- A61B8/445—Details of catheter construction
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
- A61B8/44—Constructional features of the ultrasonic, sonic or infrasonic diagnostic device
- A61B8/4483—Constructional features of the ultrasonic, sonic or infrasonic diagnostic device characterised by features of the ultrasound transducer
- A61B8/4494—Constructional features of the ultrasonic, sonic or infrasonic diagnostic device characterised by features of the ultrasound transducer characterised by the arrangement of the transducer elements
Definitions
- the present invention relates to intravascular ultrasonic catheter arrangements and more particularly to the construction and manufacture of an ultrasonic transducer array for mounting at or near the distal end of a catheter arrangement.
- ultrasonic transducer array With the kinds of ultrasonic transducer array to which the present invention relates, its very small size (typically one millimetre in diameter) means that there are considerable technological problems to overcome in order to firstly make it possible to manufacture the array at an acceptable yield level and secondly to provide the array and its associated control circuitry/software with an acceptable performance particularly as far as the definition of images obtained is concerned.
- Ultrasound arrays to which the present invention is applicable have typically employed piezoelectric materials such as modified PZT (lead zirconate titanate) for the transduction of a radio frequency (rf) electrical signal into an ultrasonic signal.
- modified PZT lead zirconate titanate
- rf radio frequency
- the manufacturing operations such as lapping, polishing, dicing and electroding (i.e. securing electrodes to the elements of the array) introduce defects which are associated both with the bulk body of the transducer element material and its surface. In particular microcracks are generated which significantly reduce the macroscopic fracture resistance of the material.
- One object of the present invention therefore is to overcome or reduce the above mentioned manufacturing problems whilst at the same time not prejudicing the operational performance of the ultrasonic transducer arrangement.
- these relaxor ferroelectrics can exhibit a very large pseudo piezoelectric response, typically d.sub.33-3,000 pC/N.
- such materials are available with high values of permittivity (e.g. e.sub.r-12000), with small grain size (e.g. 1-2 .mu.m) and with improved fracture toughness.
- Fine grain microstructures will reduce surface microcrack dimensions and thus the overall tendency to fracture.
- a further advantageous feature of an electrostrictive material is that it is unpolarised in the absence of the bias field. This means that processing steps involving heat and high local stresses will not result in the polarising degradation which can occur with piezoelectric materials such as PZT.
- the elements of the transducer array are manufactured from a non-polymeric electrostrictive material.
- control arrangement for energising such an array and processing signals derived therefrom comprises means for applying a bias voltage to the elements of the array, to render those elements significantly piezoelectric, and means for transmitting and receiving signals in relation to those transducer elements only when the bias voltage is being applied.
- a single block of PZT is mounted on a substrate in-the-flat.
- a plurality of saw cuts are then made in the PZT block to define the individual transducer elements of which there are typically sixty-four.
- the arrangement thus produced is then folded into the final cylindrical configuration to thus produce an annular ultrasonic transducer array made up of the plurality of transducer elements.
- the aforementioned saw cuts are continued down to some extent into the polyimide substrate on which the transducer material is mounted. This extent is critical because it has to be sufficient to allow the assembly to be folded easily whilst at the same time not weakening the substrate to the point where it will fracture.
- the sawing step in the manufacturing process has to be carried out to extremely small tolerances.
- the saw cuts should have flat-bottoms but this is difficult to achieve in practice.
- the bottom of the saw cut is hereinafter referred to as the “slot bottom”.
- FIG. 1 is a perspective view of the ultrasonic transducer/multiplexer assembly in-the-flat as shown in FIG. 4 of the applicant's European Patent No 0 671 221;
- FIG. 2 is a perspective view of the assembly of FIG. 1 in its final cylindrical configuration as shown in FIG. 8 of the applicant's European Patent No 0 671 221;
- FIG. 3 is a fragmentary perspective view to an enlarged scale of one embodiment of the present invention showing part of a transducer array and associated multiplexer arrangement in the flat condition prior to its wrapping into the its cylindrical configuration;
- FIG. 4 illustrates the basic electronic address circuit employed with the present invention.
- FIGS. 5 to 10 illustrate the various stages, according to the present invention, for forming the slot bottoms in the ultrasonic transducer.
- FIGS. 1 and 2 are identical to FIGS. 1 and 2
- a transducer array 110 and multiplexer 111 arrangement is first manufactured in-the-flat as shown in FIG. 1 . It is then wrapped or rolled into the cylindrical configuration shown in FIG. 2 .
- the transducer array 110 comprises sixty four transducer elements 112 which are electrically connected to four 16 -channels multiplexer chips 111 a, 111 b, 111 c and 111 d ( 111 b being omitted for clarity and 111 c being only partially shown) each chip being in the form of an integrated circuit.
- the advantage of initially manufacturing the assembly shown in FIG. 1 in-the-flat is that it is easier to manufacture because firstly forming the various components in-the-flat rather than on a cylindrical surface is inherently easier and secondly it is possible to use standard production equipment. More particularly standard printed circuit and integrated circuit production methods can be employed.
- a further advantage, is that the thickness of flat material is easier to control to high accuracy than the wall thickness of cylindrical components.
- the transducer array 110 consist of functionally discrete ceramic elements mounted on a flexible substrate 113 .
- Each multiplexer 111 a, 111 b, 111 c and 111 d is in the form of an integrated circuit and this integrated circuit can itself be flip-chip bonded to a circuit comprising electrical connections 114 which are formed on the substrate 113 by means of known printed circuit techniques.
- the transducer array 110 which consists of functionally discrete ceramic elements, is manufactured using the following steps.
- the polyimide substrate material 113 is plated on both sides, with a 1-2 micron thickness of copper, typically by a two stage process in which vacuum deposition or sputtering is used to give a thin base coat of good allocation, and chemical plating techniques to increase the copper thickness to the desired value.
- the conductive tracks 114 are then formed in the layer of copper on one side of the substrate by a standard photolithography technique followed by chemical etching or ion-beam milling to form the circuit pattern.
- the bonding is effected by a suitable adhesive which could comprise a low viscosity epoxy resin.
- the polyimide substrate 113 has a copper layer on its bottom surface.
- the piezo-electric transducer array in use, would be energised through the copper layer, the upper metalised layer on the top of the piezoelectric ceramic transducer block 112 forming an earth return path and being electrically connected to the other copper layer to thus form a common return path.
- the substrate 113 is provided with slots 115 to facilitate the folding or wrapping of the substrate into a cylindrical configuration as shown in FIG. 2 .
- FIG. 2 the same reference numerals have been used as in FIG. 1 in order to designate the same items.
- the cylindrical transducer array and multiplexer arrangement is mounted on a flexible plastic tubular body member 201 which itself is mounted on the main flexible plastic tubular body of the catheter (not shown).
- the usual guide wire is shown at 202 .
- the transducer array 310 itself is fabricated from a PMN (lead magnesium niobate) and the polyimide substrate 313 carries a block 316 of high permitivity low loss ceramic associated with each of the four multiplexers (only 331 b is shown).
- Each block 316 functions as a common rf connection between the associated multiplexer and the associated group of sixteen transducer elements for coupling the rf signal to the transducer array input tracks 314 .
- each ceramic block could be divided into sixteen physically articulated sections, one for each channel associated with each of the sixteen transducer elements.
- the block 316 capacitatively couples the multiplexer 331 b to the individual channels of the array 310 by means of a high permitivity ceramic layer.
- the transducer array 310 itself is fabricated from a PMN (lead magnesium niobate) and the polyimide substrate 313 carries a block 316 of high permittivity low loss ceramic associated with each of the four multiplexers (only 331 b is shown).
- Each block 316 functions as a common rf connection between the associated multiplexer and the associated group of sixteen transducer elements for coupling the rf signal to the transducer array input tracks 314 .
- each ceramic block could be divided into sixteen physically articulated sections, one for each channel associated with each of the sixteen transducer elements.
- the block 316 capacitatively couples the multiplexer 331 b to the individual channels of the array 310 by means of a high permittivity ceramic layer.
- the transducer array 310 may be made from an electrostrictive or equivalent ferroelectric relaxor material.
- the multiplexer arrangement is configured to transmit a DC bias voltage to the array 310 .
- FIG. 3 illustrates a single quadrant of the IVUS catheter and one method of coupling the rf signal to the array.
- This method is directly applicable to the existing configuration of the “wrap”.
- the principle of operation is as follows.
- PMN requires a bias field to become significantly piezoelectric and thus the PMN elements only transmit and receive when the bias voltage is applied through the multiplexer.
- the rf signals can therefore be applied simultaneously (but not continuously) to all elements of the array 310 ; because only those transducer elements which have the bias field applied to them will transform the rf signal into an ultrasonic signal.
- the drive and interrogation of the array 310 is thus by means of the multiplexed bias voltage which opens windows during which the rf signal can be effective.
- FIG. 4 shows the essentials of the electronic addressing of two channels of the array.
- FIG. 4 illustrates part of the control circuit for two of the transducer elements 410 a and 410 b.
- the multiplexer 411 is configured to transmit a DC bias voltage 417 to the elements 410 a and 410 b of the array. 410 b of the array.
- the high permitivity ceramic block 416 functions as a common rf connection between the multiplexer 411 and the array and capacitatively couples the latter to the former.
- U PZT can act as such a component.
- the slot bottom problem relates primarily to the rounded shape of the cutting edge of the dicing blade which is reproduced approximately in the array slot-bottom.
- the present invention relates to the fabrication of rectangular slot bottoms in the polyimide substrate by a laser ablation process prior to array dicing.
- the flex-circuit slot bottom is ablated using the flex-circuit itself as a mask, which automatically aligns the slot bottoms with the flex-circuit.
- the flex-circuit is utilised as a mask for laser ablation.
- the transducer area of the flex-circuit contains copper tracks 51 of width equal to the element width, namely 30 .mu.m formed in a polyimide matching layer 50 .
- These tracks 51 in conjunction with a rectangular aperture step 52 , defining an overall exposure window, are used as a mask for laser ablation of rectangular trenches 53 of width .about.17 .mu.m in the polyamide flex-circuit.
- the intensity-time exposure parameters for the laser yield reproducible slot bottoms 54 . It may be advantageous to thicken the tracks 51 to 1-2 .mu.m by use of nickel plating in the transducer area, as on the remainder of the flex-circuit.
- the whole flex-circuit 51 is coated with a layer of photoresist 55 .about.5 .mu.m thick using a spinning technique, giving the result illustrated in FIG. 7 . It is only necessary that the trenches 53 be partly filled with the photoresist material 55 .
- the photoresist layer 55 is ablated and the .about.5 .mu.m thick layer 55 a covering the metal tracks 51 is removed. This will leave a photoresist layer 55 b in the trench-bottoms, as illustrated in FIG. 8 .
- the same result can also be achieved by “wicking” photoresist (or an alternative slot bottom fill substance) along the trenches (i.e. relying on capillary action to cause the resist to move along the trenches to substantially fill them) from one end, or by selective ultra violet curing of the photoresist layer means of an auxiliary mask.
- the PZT transducer array is then fabricated on top of the arrangement shown in FIG. 8 . This fabrication is illustrated in FIGS. 9 and 10 .
- a PZT block 91 is bonded by adhesive 92 to the layer 50 using known adhesive techniques. This is illustrated in FIG. 9 .
- the adhesive 92 will fill the trenches 54 above the photoresist layer 55 b and will not penetrate to the bottom of the slot bottom 91 a, 91 b, 91 c, 91 d etc.
- the individual PZT elements of the transducer array are diced in the normal way using a diamond saw to create the slots, ensuring the blade penetrates the polyimide by approximately two thirds of its kerf depth (e.g. 10 .mu.m if the polyimide kerf is 15 .mu.m deep). This is illustrated in FIG. 10 , and shows the saw cuts penetrating into the temporary key-fill material (photoresist) 55 b, the saw being indicated at 101 in broken lines.
- the polyimide slot bottoms are cleaned with a suitable solvent to remove the residual photoresist 55 b and create an empty flat bottomed slot bottom.
- a reproducible slot bottom can be created in the polyimide without melting or tearing of the plastic and without the risk of depth overshoot inherent in the existing sawing process. That is, the laser will ablate a certain thickness of polyimide irrespective of whether or not the flex-circuit is flat, whereas the sawing process depends critically on mounting-fixture flatness, flex circuit planarity and flex-circuit thickness variability.
- a rectangular slot bottom is the optimum for strain relief on wrapping and leads to significantly reduced risk of PZT fracture of wrapping stresses.
- the ceramic carrier will be a low-density, low-cost PZT material, or some other machineable ceramic such as Macor or Shapal.
- the wax will be of a type soluble in a safe organic solvent, and capable of being pressed under controlled, elevated-temperature, conditions into a thin, uniform layer.
Abstract
Devices, systems, and methods for intravascular ultrasonic imaging are provided. In one embodiment, an apparatus for intravascular ultrasonic imaging is provided. The apparatus includes a flexible elongate member sized for insertion within a vasculature; an ultrasonic transducer array, mounted proximate a distal end of the flexible elongate member, wherein transducer elements of the ultrasonic transducer array comprise a non-polymeric electrostrictive material; and a high permittivity ceramic member that signally couples a common radiofrequency signal source to all elements of the transducer array simultaneously such that the common radiofrequency signal is provided through the ceramic member to all the transducer elements of the ultrasonic transducer array and a bias field is selectively transmitted to one or more of the transducer elements such that only transducer elements having the bias field applied to them will transform the common radiofrequency signal into an ultrasonic signal.
Description
- This application is a continuation of U.S. patent application Ser. No. 10/398,967 filed on Dec. 17, 2004, now U.S. Pat. No. 8,118,742, which is a national stage entry of PCT/GB01/04548 filed on Oct. 11, 2001, which claims priority to GB Patent Application No. 0025250.2 filed on Oct. 14, 2000, each of which is hereby incorporated by reference in its entirety.
- The present invention relates to intravascular ultrasonic catheter arrangements and more particularly to the construction and manufacture of an ultrasonic transducer array for mounting at or near the distal end of a catheter arrangement.
- Examples of the types of intravascular ultrasonic catheter arrangements to which the present invention may be applied are disclosed in our earlier United Kingdom Patent Nos. 2,221,267; 2,233,094 and our U.S. Pat. Nos. 5,081,993; 5,257,629 and 5,456,259.
- With the kinds of ultrasonic transducer array to which the present invention relates, its very small size (typically one millimetre in diameter) means that there are considerable technological problems to overcome in order to firstly make it possible to manufacture the array at an acceptable yield level and secondly to provide the array and its associated control circuitry/software with an acceptable performance particularly as far as the definition of images obtained is concerned.
- Ultrasound arrays to which the present invention is applicable have typically employed piezoelectric materials such as modified PZT (lead zirconate titanate) for the transduction of a radio frequency (rf) electrical signal into an ultrasonic signal. In very high frequency applications, such as are relevant to the present invention, the performance of such piezoelectric arrays is limited by the grain size of the piezoelectric ceramic material. This is because, due to the very small size of the array, the grain size of the material begins to become comparable with the dimensions of the array elements.
- Furthermore, because of the crystalline nature of the material from which the elements of the array are manufactured, the manufacturing operations such as lapping, polishing, dicing and electroding (i.e. securing electrodes to the elements of the array) introduce defects which are associated both with the bulk body of the transducer element material and its surface. In particular microcracks are generated which significantly reduce the macroscopic fracture resistance of the material.
- One object of the present invention therefore is to overcome or reduce the above mentioned manufacturing problems whilst at the same time not prejudicing the operational performance of the ultrasonic transducer arrangement.
- In order to try and overcome the above discussed problems the inventors have therefore researched alternative materials for the manufacture of ultrasonic transducer elements and have concluded that a class of materials that would be suitable are those known as electrostrictive materials such as “relaxor ferroelectrics”.
- It has been found that these can exhibit a large pseudo-piezoelectric response if a suitable d.c. electric bias field is applied to them. These materials have a finer microstructure than the known PZT material discussed earlier together with enhanced fracture toughness. An example of a relaxor ferroelectric material is modified PMN (lead magnesium niobate).
- As indicated these relaxor ferroelectrics can exhibit a very large pseudo piezoelectric response, typically d.sub.33-3,000 pC/N. In addition such materials are available with high values of permittivity (e.g. e.sub.r-12000), with small grain size (e.g. 1-2 .mu.m) and with improved fracture toughness.
- High values of permittivity will, in general, allow improved ultra-small array elements from the interrogating electronics by reducing the element impedance.
- Fine grain microstructures will reduce surface microcrack dimensions and thus the overall tendency to fracture. A further advantageous feature of an electrostrictive material is that it is unpolarised in the absence of the bias field. This means that processing steps involving heat and high local stresses will not result in the polarising degradation which can occur with piezoelectric materials such as PZT.
- Thus according to a first aspect of the present invention, in an ultrasonic transducer array arrangement suitable for mounting on a catheter, the elements of the transducer array are manufactured from a non-polymeric electrostrictive material.
- According to a second aspect of the present invention the control arrangement for energising such an array and processing signals derived therefrom comprises means for applying a bias voltage to the elements of the array, to render those elements significantly piezoelectric, and means for transmitting and receiving signals in relation to those transducer elements only when the bias voltage is being applied.
- With this arrangement it is thus possible to apply the rf signals simultaneously (but not continuously) to all elements of the array because only those transducer elements which have the bias field applied to them will transform the rf signal into the correct ultrasonic signal. The drive and interrogation of the array is thus by means of the multiplexed bias voltage which opens “windows” during which the rf signal can be effective. The rf signal is turned off during the receive interval for a given channel in the usual manner.
- The advantage of coupling the rf signal in this way are (i) the signal losses in the multiplexer are now only seen during the receive mode and (ii) the rf signal size is not limited by the multiplexer.
- So far the present invention has been discussed in relation to the material from which the transducer elements are manufactured and this aspect of the invention is applicable irrespective of other steps in the manufacture of the ultrasonic transducer arrangement.
- There will now be discussed a further aspect of the present invention which relates to the manufacturing process employed for producing an ultrasonic transducer array of the kind previously outlined, this further aspect being independent of the material employed for the manufacture of the transducer array elements.
- One method of manufacturing an annular transducer array of the kind to which the present invention relates is disclosed in our European Patent No 0 671 221 in which the transducer array, and its associated multiplexer/control circuitry, is manufactured in-the-flat initially and then transformed into a cylindrical configuration.
- In such a manufacturing method the functionally independent elements of the eventual annular array are produced by the following method.
- A single block of PZT is mounted on a substrate in-the-flat. A plurality of saw cuts are then made in the PZT block to define the individual transducer elements of which there are typically sixty-four. The arrangement thus produced is then folded into the final cylindrical configuration to thus produce an annular ultrasonic transducer array made up of the plurality of transducer elements. In order to facilitate folding step, the aforementioned saw cuts are continued down to some extent into the polyimide substrate on which the transducer material is mounted. This extent is critical because it has to be sufficient to allow the assembly to be folded easily whilst at the same time not weakening the substrate to the point where it will fracture.
- Because of the extremely small size of the arrangement just described the sawing step in the manufacturing process has to be carried out to extremely small tolerances. In addition, for the best operating characteristics, the saw cuts should have flat-bottoms but this is difficult to achieve in practice. The bottom of the saw cut is hereinafter referred to as the “slot bottom”.
- Therefore, according to a further aspect of the present invention in a manufacturing process for producing an ultrasonic transducer array in which a block of transducer material is divided into a plurality of discrete transducer elements and is mounted on a flexible substrate, flexing slots are formed in the substrate between adjacent transducer elements by means of a laser beam,
- This enables the depth of the cut to be more easily controlled, when compared with using a saw, and it also makes it possible to more easily approach the ideal rectangular shape for the bottom of the slot, or “slot bottom”.
- How the invention may be carried out will now be described by way of example only with reference to the accompanying drawings in which:
-
FIG. 1 is a perspective view of the ultrasonic transducer/multiplexer assembly in-the-flat as shown inFIG. 4 of the applicant's European Patent No 0 671 221; -
FIG. 2 is a perspective view of the assembly ofFIG. 1 in its final cylindrical configuration as shown inFIG. 8 of the applicant's European Patent No 0 671 221; -
FIG. 3 is a fragmentary perspective view to an enlarged scale of one embodiment of the present invention showing part of a transducer array and associated multiplexer arrangement in the flat condition prior to its wrapping into the its cylindrical configuration; -
FIG. 4 illustrates the basic electronic address circuit employed with the present invention; and -
FIGS. 5 to 10 illustrate the various stages, according to the present invention, for forming the slot bottoms in the ultrasonic transducer. -
FIGS. 1 and 2 - A
transducer array 110 andmultiplexer 111 arrangement is first manufactured in-the-flat as shown inFIG. 1 . It is then wrapped or rolled into the cylindrical configuration shown inFIG. 2 . - The
transducer array 110 comprises sixty fourtransducer elements 112 which are electrically connected to four 16-channels multiplexer chips - The advantage of initially manufacturing the assembly shown in
FIG. 1 in-the-flat is that it is easier to manufacture because firstly forming the various components in-the-flat rather than on a cylindrical surface is inherently easier and secondly it is possible to use standard production equipment. More particularly standard printed circuit and integrated circuit production methods can be employed. A further advantage, is that the thickness of flat material is easier to control to high accuracy than the wall thickness of cylindrical components. - The
transducer array 110 consist of functionally discrete ceramic elements mounted on aflexible substrate 113. - Each
multiplexer electrical connections 114 which are formed on thesubstrate 113 by means of known printed circuit techniques. - The
transducer array 110 which consists of functionally discrete ceramic elements, is manufactured using the following steps. - The
polyimide substrate material 113 is plated on both sides, with a 1-2 micron thickness of copper, typically by a two stage process in which vacuum deposition or sputtering is used to give a thin base coat of good allocation, and chemical plating techniques to increase the copper thickness to the desired value. - The
conductive tracks 114 are then formed in the layer of copper on one side of the substrate by a standard photolithography technique followed by chemical etching or ion-beam milling to form the circuit pattern. - A block of piezo-
electric material 112 having the desired radial thickness of the final transducer elements and coated on both sides by a metallisation layer, is bonded in one piece to an area of the copper layer which is shaped to define a connection pad on the substrate. The bonding is effected by a suitable adhesive which could comprise a low viscosity epoxy resin. - The
polyimide substrate 113 has a copper layer on its bottom surface. - The piezo-electric transducer array, in use, would be energised through the copper layer, the upper metalised layer on the top of the piezoelectric
ceramic transducer block 112 forming an earth return path and being electrically connected to the other copper layer to thus form a common return path. - The
substrate 113 is provided withslots 115 to facilitate the folding or wrapping of the substrate into a cylindrical configuration as shown inFIG. 2 . - In
FIG. 2 the same reference numerals have been used as inFIG. 1 in order to designate the same items. - The cylindrical transducer array and multiplexer arrangement is mounted on a flexible plastic
tubular body member 201 which itself is mounted on the main flexible plastic tubular body of the catheter (not shown). The usual guide wire is shown at 202. -
FIGS. 3 and 4 - The
transducer array 310 itself is fabricated from a PMN (lead magnesium niobate) and thepolyimide substrate 313 carries ablock 316 of high permitivity low loss ceramic associated with each of the four multiplexers (only 331 b is shown). Eachblock 316 functions as a common rf connection between the associated multiplexer and the associated group of sixteen transducer elements for coupling the rf signal to the transducer array input tracks 314. In a modification each ceramic block could be divided into sixteen physically articulated sections, one for each channel associated with each of the sixteen transducer elements. Theblock 316 capacitatively couples themultiplexer 331 b to the individual channels of thearray 310 by means of a high permitivity ceramic layer. - The
transducer array 310 itself is fabricated from a PMN (lead magnesium niobate) and thepolyimide substrate 313 carries ablock 316 of high permittivity low loss ceramic associated with each of the four multiplexers (only 331 b is shown). Eachblock 316 functions as a common rf connection between the associated multiplexer and the associated group of sixteen transducer elements for coupling the rf signal to the transducer array input tracks 314. In a modification each ceramic block could be divided into sixteen physically articulated sections, one for each channel associated with each of the sixteen transducer elements. Theblock 316 capacitatively couples themultiplexer 331 b to the individual channels of thearray 310 by means of a high permittivity ceramic layer. - The
transducer array 310 may be made from an electrostrictive or equivalent ferroelectric relaxor material. - The multiplexer arrangement is configured to transmit a DC bias voltage to the
array 310. -
FIG. 3 illustrates a single quadrant of the IVUS catheter and one method of coupling the rf signal to the array. This method is directly applicable to the existing configuration of the “wrap”. The principle of operation is as follows. PMN requires a bias field to become significantly piezoelectric and thus the PMN elements only transmit and receive when the bias voltage is applied through the multiplexer. The rf signals can therefore be applied simultaneously (but not continuously) to all elements of thearray 310; because only those transducer elements which have the bias field applied to them will transform the rf signal into an ultrasonic signal. The drive and interrogation of thearray 310 is thus by means of the multiplexed bias voltage which opens windows during which the rf signal can be effective. Clearly the rf signal but not the dc bias is turned off during the receive interval for a given channel. Advantages of coupling the rf signal in this way are (i) the signal losses in the multiplexer are now only seen in receive and (ii) the rf signal size is not limited by the multiplexer.FIG. 4 shows the essentials of the electronic addressing of two channels of the array. -
FIG. 4 illustrates part of the control circuit for two of thetransducer elements - The
multiplexer 411 is configured to transmit aDC bias voltage 417 to theelements - The high permitivity
ceramic block 416 functions as a common rf connection between themultiplexer 411 and the array and capacitatively couples the latter to the former. U PZT can act as such a component. -
FIGS. 5 to 10 - Existing array-dicing processes have problems with height-control and the shape of the slot bottom. The height-control problem is exacerbated by:
- (i) the non-uniformity of the polyimide substrate;
- (ii) the difficulties of vacuum-mounting an undulating, flexible substrate containing rigid components with stressed adhesive interfaces; and
- (iii) dicing-blade wear. The slot bottom problem relates primarily to the rounded shape of the cutting edge of the dicing blade which is reproduced approximately in the array slot-bottom.
- Flat-bottomed blades are difficult to achieve in practice because both the blade-dressing procedure prior to dicing and the blade-wear of the dicing process itself tend to yield a rounded blade-edged profile. The rounded profile, leading to a similar shape in the polyimide slot bottom, is undesirable from the point of view of the wrap-mechanics and acoustic performance of the final array. Furthermore, any subsequent processing of a saw-cut polyimide slot bottom (e.g. by laser ablation) would necessarily begin from the “parabolic” shape left by the sawing process, and may not result in the desired rectangular shape. The process issues to be addressed are therefore:
- (i) how can shape-controlled slots be cut into a thin, flexible and variable carrier film?
- (ii) can a pre-cut flex-circuit slot bottom, be ablated accurately using the flex-circuit itself as a mask?
- The present invention relates to the fabrication of rectangular slot bottoms in the polyimide substrate by a laser ablation process prior to array dicing. The flex-circuit slot bottom is ablated using the flex-circuit itself as a mask, which automatically aligns the slot bottoms with the flex-circuit.
- The following process achieves a rectangular slot bottom in the polyimide.
- The flex-circuit is utilised as a mask for laser ablation. The transducer area of the flex-circuit contains copper tracks 51 of width equal to the element width, namely 30 .mu.m formed in a
polyimide matching layer 50. Thesetracks 51 in conjunction with arectangular aperture step 52, defining an overall exposure window, are used as a mask for laser ablation ofrectangular trenches 53 of width .about.17 .mu.m in the polyamide flex-circuit. The intensity-time exposure parameters for the laser yieldreproducible slot bottoms 54. It may be advantageous to thicken thetracks 51 to 1-2 .mu.m by use of nickel plating in the transducer area, as on the remainder of the flex-circuit. - The whole flex-
circuit 51 is coated with a layer of photoresist 55 .about.5 .mu.m thick using a spinning technique, giving the result illustrated inFIG. 7 . It is only necessary that thetrenches 53 be partly filled with the photoresist material 55. - The photoresist layer 55 is ablated and the .about.5 .mu.m
thick layer 55 a covering the metal tracks 51 is removed. This will leave aphotoresist layer 55 b in the trench-bottoms, as illustrated inFIG. 8 . The same result can also be achieved by “wicking” photoresist (or an alternative slot bottom fill substance) along the trenches (i.e. relying on capillary action to cause the resist to move along the trenches to substantially fill them) from one end, or by selective ultra violet curing of the photoresist layer means of an auxiliary mask. - Having accurately formed the slot bottom 54 using a laser (
FIGS. 5 to 8 ), the PZT transducer array is then fabricated on top of the arrangement shown inFIG. 8 . This fabrication is illustrated inFIGS. 9 and 10 . - A
PZT block 91 is bonded by adhesive 92 to thelayer 50 using known adhesive techniques. This is illustrated inFIG. 9 . The adhesive 92 will fill thetrenches 54 above thephotoresist layer 55 b and will not penetrate to the bottom of the slot bottom 91 a, 91 b, 91 c, 91 d etc. There is anupper metallisation layer 93 topped by apolyimide ground plane 94. - The individual PZT elements of the transducer array are diced in the normal way using a diamond saw to create the slots, ensuring the blade penetrates the polyimide by approximately two thirds of its kerf depth (e.g. 10 .mu.m if the polyimide kerf is 15 .mu.m deep). This is illustrated in
FIG. 10 , and shows the saw cuts penetrating into the temporary key-fill material (photoresist) 55 b, the saw being indicated at 101 in broken lines. - The polyimide slot bottoms are cleaned with a suitable solvent to remove the
residual photoresist 55 b and create an empty flat bottomed slot bottom. - The advantages of the modified process are the following:
- (i) A reproducible slot bottom can be created in the polyimide without melting or tearing of the plastic and without the risk of depth overshoot inherent in the existing sawing process. That is, the laser will ablate a certain thickness of polyimide irrespective of whether or not the flex-circuit is flat, whereas the sawing process depends critically on mounting-fixture flatness, flex circuit planarity and flex-circuit thickness variability.
- (ii) A rectangular slot bottom is the optimum for strain relief on wrapping and leads to significantly reduced risk of PZT fracture of wrapping stresses.
- (iii) A rectangular slot bottom is in many cases the optimum for reduction of acoustic cross-talk.
- (iv) The modified process removes the need for stringent height-control in the dicing process, and thus removes a demanding process parameter involving significant cost.
- As a further aspect of the present invention there will now be described a modification of the transducer fabrication technique which could address both the shape and depth of the slot bottom.
- This modified method is as follows:
- (i) Double-metalize the ground-plane polyimide and wax both this and the ceramic spacer material to a ceramic carrier block. The ceramic carrier will be a low-density, low-cost PZT material, or some other machineable ceramic such as Macor or Shapal. The wax will be of a type soluble in a safe organic solvent, and capable of being pressed under controlled, elevated-temperature, conditions into a thin, uniform layer.
- (ii) Bond the pre-poled, metalized, transducer block, of dimensions 3.2.times.0.8.times.0.05, to the ground-plane electrode and, the ground-plane electrode to the spacer using Hysol epoxy in a purpose-built assembly press.
- (iii) Dice the transducer block whilst on the sacrificial ceramic carrier. The slot bottom depth will be such as to penetrate the ceramic carrier by a few tens of microns. By this means parallel-sided cuts in the PZT and ground-plane are achieved and each full array width is defined.
- (iv) Invert the ceramic carrier block, ground-planes and transducer plates over the polyimide matching layer (flex-circuit) and epoxy bond in a temperature and pressure controlled press. This step involves accurate alignment of the transducer array and the flex-circuit. The alignment is achieved by dicing through the carrier ceramic block at, or close to, the perimeter of the transducer array, in order to allow the individual positioning of these arrays on the flex-circuit diaphragm. Alternative bonding processes are flip-chip solder and indium-gold. Epoxy-bonding would involve excess adhesive which may interfere with the laser ablation process.
- (v) Remove the ceramic carrier by immersion of the flex-circuit in the chosen solvent. Remaining on the flex-circuit are the diced PZT arrays with their diced ground-planes, each array bonded to the polyimide flex circuit. Since the exposed surface of the ground-plane is metalized it acts as a reflector of the laser beam, whereas the polyimide does not.
- (vi) Use the diced PZT-array and ground-plane assembly as a mask for ablation of the polyimide flex-circuit. Since the exposed surface of the ground-plane is metalized it acts as a reflector of the laser beam, whereas the polyimide in the slot bottom is exposed to the full-power of the laser and is ablated. Clearly, since the slot bottom shape is rectangular before ablation, there is a much greater chance of controlling the thinning to give, say, a 0.005 uniform layer of polyimide remaining after ablation. An alternative to this is to ablate the flex circuit before assembly using the tracks in the transducer area as a mask.
Claims (20)
1-18. (canceled)
19. An apparatus for intravascular ultrasonic imaging, the apparatus comprising:
a flexible elongate member sized for insertion within a vasculature;
an ultrasonic transducer array, mounted proximate a distal end of the flexible elongate member, wherein transducer elements of the ultrasonic transducer array comprise a non-polymeric electrostrictive material; and
a high permitivity ceramic member that signally couples a common radiofrequency signal source to all elements of the transducer array simultaneously such that the common radiofrequency signal is provided through the ceramic member to all the transducer elements of the ultrasonic transducer array and a bias field is selectively transmitted to one or more of the transducer elements such that only transducer elements having the bias field applied to them will transform the common radiofrequency signal into an ultrasonic signal.
20. The apparatus of claim 19 , wherein the electrostrictive material is a relaxor ferroelectric material.
21. The apparatus of claim 20 , wherein the electrostrictive material comprises lead magnesium niobate.
22. The apparatus of claim 19 , further comprising a multiplexer arrangement through which the bias field is selectively applied to one or more of the transducer elements and through which echo signals received by the transducer array are passed to the proximal end of the flexible elongate member.
23. The apparatus of claim 22 , wherein the multiplexer arrangement comprises a plurality of integrated circuits.
24. The apparatus as claimed in claim 23 , wherein the transducer array is arranged in a substantially cylindrical configuration.
25. The apparatus of claim 23 , wherein adjacent integrated circuits are spaced from one another by a slot.
26. The apparatus of claim 23 , wherein the integrated circuits are flip-chip bonded to an electrical circuit.
27. The apparatus of claim 26 , wherein the electrical circuit comprises a printed circuit.
28. The apparatus of claim 19 , wherein the transducer array comprises:
a substrate;
electrically conductive tracks on the substrate; and
a set of individual transducer array elements created by forming slots in a piezoelectric block.
29. The apparatus of claim 28 , further comprising at least one multiplexer circuit coupled to the electrically conductive tracks.
30. The apparatus of claim 28 , further comprising slot bottoms formed in the substrate adjacent the electrically conductive tracks.
31. The apparatus of claim 30 , wherein the slot bottoms are formed with a laser.
32. The apparatus of claim 19 , wherein the flexible elongate member is a catheter.
33. The apparatus of claim 19 , wherein the high permitivity ceramic member capacitatively couples the common radiofrequency signal source to signal lines that selectively carry a DC bias voltage signal to individual ones of the elements of the transducer array.
34. The apparatus of claim 33 , wherein a multiplexer selectively provides the DC bias voltage signal to individual ones of the transducer elements of the transducer array.
35. The apparatus of claim 33 , wherein the electrostrictive material of the transducer elements comprises ferroelectric relaxor material.
36. The apparatus of claim 33 , wherein the electrostrictive material of the transducer elements comprises lead magnesium niobate.
37. An apparatus for intravascular ultrasonic imaging, the apparatus comprising:
a flexible elongate member sized for insertion within a vasculature;
an ultrasonic transducer array mounted proximate a distal end of the flexible elongate member, the array comprising a plurality of ultrasonic transducer elements, each comprising a non-polymeric electrostrictive material;
a multiplexer configured to selectively transmit a DC bias voltage to the plurality of ultrasonic transducer elements; and
a common high permitivity ceramic member configured to simultaneously electrically couple all the transducer elements to each other and to a common radiofrequency signal source;
wherein the common radiofrequency signal is provided through the ceramic member to all of the transducer elements of the ultrasonic transducer array and the DC bias voltage is selectively transmitted to one or more of the transducer elements such that only transducer elements having the DC bias voltage applied to them will transform the common radiofrequency signal into an ultrasonic signal.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/401,574 US20120232400A1 (en) | 2000-10-14 | 2012-02-21 | Intravascular Ultrasonic Catheter Arrangements |
Applications Claiming Priority (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB0025250A GB2368123A (en) | 2000-10-14 | 2000-10-14 | Electrostrictive ultrasonic transducer array suitable for catheter |
GB0025250.2 | 2000-10-14 | ||
PCT/GB2001/004548 WO2002032315A1 (en) | 2000-10-14 | 2001-10-11 | Intravascular ultrasonic catheter arrangements |
US10/398,967 US8118742B2 (en) | 2000-10-14 | 2001-10-11 | Intravascular ultrasonic catheter arrangements |
US13/401,574 US20120232400A1 (en) | 2000-10-14 | 2012-02-21 | Intravascular Ultrasonic Catheter Arrangements |
Related Parent Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/GB2001/004548 Continuation WO2002032315A1 (en) | 2000-10-14 | 2001-10-11 | Intravascular ultrasonic catheter arrangements |
US10/398,967 Continuation US8118742B2 (en) | 2000-10-14 | 2001-10-11 | Intravascular ultrasonic catheter arrangements |
Publications (1)
Publication Number | Publication Date |
---|---|
US20120232400A1 true US20120232400A1 (en) | 2012-09-13 |
Family
ID=9901318
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/398,967 Active 2025-03-20 US8118742B2 (en) | 2000-10-14 | 2001-10-11 | Intravascular ultrasonic catheter arrangements |
US13/401,574 Abandoned US20120232400A1 (en) | 2000-10-14 | 2012-02-21 | Intravascular Ultrasonic Catheter Arrangements |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/398,967 Active 2025-03-20 US8118742B2 (en) | 2000-10-14 | 2001-10-11 | Intravascular ultrasonic catheter arrangements |
Country Status (8)
Country | Link |
---|---|
US (2) | US8118742B2 (en) |
EP (1) | EP1324702B1 (en) |
JP (1) | JP2004511290A (en) |
AT (1) | ATE266968T1 (en) |
AU (1) | AU2001294020A1 (en) |
DE (1) | DE60103417T2 (en) |
GB (1) | GB2368123A (en) |
WO (1) | WO2002032315A1 (en) |
Cited By (48)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20130227826A1 (en) * | 2012-03-05 | 2013-09-05 | Xerox Corporation | Print head transducer dicing directly on diaphragm |
WO2014099763A1 (en) | 2012-12-21 | 2014-06-26 | Jason Spencer | System and method for graphical processing of medical data |
WO2014099760A1 (en) | 2012-12-21 | 2014-06-26 | Mai Jerome | Ultrasound imaging with variable line density |
US9226711B2 (en) | 2012-12-21 | 2016-01-05 | Volcano Corporation | Laser direct structured catheter connection for intravascular device |
US9286673B2 (en) | 2012-10-05 | 2016-03-15 | Volcano Corporation | Systems for correcting distortions in a medical image and methods of use thereof |
US9292918B2 (en) | 2012-10-05 | 2016-03-22 | Volcano Corporation | Methods and systems for transforming luminal images |
US9301687B2 (en) | 2013-03-13 | 2016-04-05 | Volcano Corporation | System and method for OCT depth calibration |
US9307926B2 (en) | 2012-10-05 | 2016-04-12 | Volcano Corporation | Automatic stent detection |
US9324141B2 (en) | 2012-10-05 | 2016-04-26 | Volcano Corporation | Removal of A-scan streaking artifact |
US9360630B2 (en) | 2011-08-31 | 2016-06-07 | Volcano Corporation | Optical-electrical rotary joint and methods of use |
US9367965B2 (en) | 2012-10-05 | 2016-06-14 | Volcano Corporation | Systems and methods for generating images of tissue |
US9383263B2 (en) | 2012-12-21 | 2016-07-05 | Volcano Corporation | Systems and methods for narrowing a wavelength emission of light |
US9478940B2 (en) | 2012-10-05 | 2016-10-25 | Volcano Corporation | Systems and methods for amplifying light |
US9486143B2 (en) | 2012-12-21 | 2016-11-08 | Volcano Corporation | Intravascular forward imaging device |
US9596993B2 (en) | 2007-07-12 | 2017-03-21 | Volcano Corporation | Automatic calibration systems and methods of use |
US9612105B2 (en) | 2012-12-21 | 2017-04-04 | Volcano Corporation | Polarization sensitive optical coherence tomography system |
US9622706B2 (en) | 2007-07-12 | 2017-04-18 | Volcano Corporation | Catheter for in vivo imaging |
US9709379B2 (en) | 2012-12-20 | 2017-07-18 | Volcano Corporation | Optical coherence tomography system that is reconfigurable between different imaging modes |
US9730613B2 (en) | 2012-12-20 | 2017-08-15 | Volcano Corporation | Locating intravascular images |
US9770172B2 (en) | 2013-03-07 | 2017-09-26 | Volcano Corporation | Multimodal segmentation in intravascular images |
US20170290562A1 (en) * | 2012-05-11 | 2017-10-12 | Volcano Corporation | Ultrasound catheter for imaging and blood flow measurement |
US9858668B2 (en) | 2012-10-05 | 2018-01-02 | Volcano Corporation | Guidewire artifact removal in images |
US9867530B2 (en) | 2006-08-14 | 2018-01-16 | Volcano Corporation | Telescopic side port catheter device with imaging system and method for accessing side branch occlusions |
US10058284B2 (en) | 2012-12-21 | 2018-08-28 | Volcano Corporation | Simultaneous imaging, monitoring, and therapy |
US10070827B2 (en) | 2012-10-05 | 2018-09-11 | Volcano Corporation | Automatic image playback |
US10191220B2 (en) | 2012-12-21 | 2019-01-29 | Volcano Corporation | Power-efficient optical circuit |
US10219887B2 (en) | 2013-03-14 | 2019-03-05 | Volcano Corporation | Filters with echogenic characteristics |
US10219780B2 (en) | 2007-07-12 | 2019-03-05 | Volcano Corporation | OCT-IVUS catheter for concurrent luminal imaging |
US10226597B2 (en) | 2013-03-07 | 2019-03-12 | Volcano Corporation | Guidewire with centering mechanism |
US10238367B2 (en) | 2012-12-13 | 2019-03-26 | Volcano Corporation | Devices, systems, and methods for targeted cannulation |
US10292677B2 (en) | 2013-03-14 | 2019-05-21 | Volcano Corporation | Endoluminal filter having enhanced echogenic properties |
US10413317B2 (en) | 2012-12-21 | 2019-09-17 | Volcano Corporation | System and method for catheter steering and operation |
US10420530B2 (en) | 2012-12-21 | 2019-09-24 | Volcano Corporation | System and method for multipath processing of image signals |
US10426590B2 (en) | 2013-03-14 | 2019-10-01 | Volcano Corporation | Filters with echogenic characteristics |
US10568586B2 (en) | 2012-10-05 | 2020-02-25 | Volcano Corporation | Systems for indicating parameters in an imaging data set and methods of use |
US10595820B2 (en) | 2012-12-20 | 2020-03-24 | Philips Image Guided Therapy Corporation | Smooth transition catheters |
US10638939B2 (en) | 2013-03-12 | 2020-05-05 | Philips Image Guided Therapy Corporation | Systems and methods for diagnosing coronary microvascular disease |
US10724082B2 (en) | 2012-10-22 | 2020-07-28 | Bio-Rad Laboratories, Inc. | Methods for analyzing DNA |
US10758207B2 (en) | 2013-03-13 | 2020-09-01 | Philips Image Guided Therapy Corporation | Systems and methods for producing an image from a rotational intravascular ultrasound device |
US10939826B2 (en) | 2012-12-20 | 2021-03-09 | Philips Image Guided Therapy Corporation | Aspirating and removing biological material |
US10942022B2 (en) | 2012-12-20 | 2021-03-09 | Philips Image Guided Therapy Corporation | Manual calibration of imaging system |
US10993694B2 (en) | 2012-12-21 | 2021-05-04 | Philips Image Guided Therapy Corporation | Rotational ultrasound imaging catheter with extended catheter body telescope |
US11026591B2 (en) | 2013-03-13 | 2021-06-08 | Philips Image Guided Therapy Corporation | Intravascular pressure sensor calibration |
US11040140B2 (en) | 2010-12-31 | 2021-06-22 | Philips Image Guided Therapy Corporation | Deep vein thrombosis therapeutic methods |
US11141063B2 (en) | 2010-12-23 | 2021-10-12 | Philips Image Guided Therapy Corporation | Integrated system architectures and methods of use |
US11154313B2 (en) | 2013-03-12 | 2021-10-26 | The Volcano Corporation | Vibrating guidewire torquer and methods of use |
US11272845B2 (en) | 2012-10-05 | 2022-03-15 | Philips Image Guided Therapy Corporation | System and method for instant and automatic border detection |
US11406498B2 (en) | 2012-12-20 | 2022-08-09 | Philips Image Guided Therapy Corporation | Implant delivery system and implants |
Families Citing this family (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7967754B2 (en) * | 2004-10-14 | 2011-06-28 | Scimed Life Systems, Inc. | Integrated bias circuitry for ultrasound imaging devices configured to image the interior of a living being |
RU2449418C2 (en) * | 2006-09-25 | 2012-04-27 | Конинклейке Филипс Электроникс Н.В. | Interconnection by flip-chip technique through open-end holes in chip |
JP4909115B2 (en) * | 2007-02-21 | 2012-04-04 | 富士フイルム株式会社 | Ultrasound probe |
CN103429166B (en) * | 2012-01-30 | 2015-06-17 | 奥林巴斯医疗株式会社 | Ultrasonic vibrator array, method for manufacturing ultrasonic vibrator array, and ultrasonic endoscope |
JP6334561B2 (en) * | 2012-12-28 | 2018-05-30 | ボルケーノ コーポレイション | Intravascular ultrasound imaging device, interface architecture, and manufacturing method |
JP6797933B2 (en) * | 2016-03-30 | 2020-12-09 | コーニンクレッカ フィリップス エヌ ヴェKoninklijke Philips N.V. | Flexible support members for intravascular diagnostic imaging devices and related devices, systems, and methods. |
WO2018060369A1 (en) * | 2016-09-29 | 2018-04-05 | Koninklijke Philips N.V. | Flexible imaging assembly for intraluminal imaging and associated devices, systems, and methods |
NZ771699A (en) * | 2018-07-31 | 2023-02-24 | Bard Inc C R | Ultrasonic system and methods |
KR102085220B1 (en) * | 2018-10-18 | 2020-03-05 | 한국과학기술연구원 | Non-invasive treatment system using intermedium |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0671221A2 (en) * | 1994-03-11 | 1995-09-13 | Intravascular Research Limited | Ultrasonic transducer array and method of manufacturing the same |
US5465725A (en) * | 1993-06-15 | 1995-11-14 | Hewlett Packard Company | Ultrasonic probe |
US5947905A (en) * | 1997-10-15 | 1999-09-07 | Advanced Coronary Intervention, Inc. | Ultrasound transducer array probe for intraluminal imaging catheter |
US6605043B1 (en) * | 1998-11-19 | 2003-08-12 | Acuson Corp. | Diagnostic medical ultrasound systems and transducers utilizing micro-mechanical components |
Family Cites Families (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4841977A (en) * | 1987-05-26 | 1989-06-27 | Inter Therapy, Inc. | Ultra-thin acoustic transducer and balloon catheter using same in imaging array subassembly |
US4917097A (en) * | 1987-10-27 | 1990-04-17 | Endosonics Corporation | Apparatus and method for imaging small cavities |
GB2212267B (en) | 1987-11-11 | 1992-07-29 | Circulation Res Ltd | Methods and apparatus for the examination and treatment of internal organs |
US4854423A (en) | 1988-07-26 | 1989-08-08 | Kelsey Hayes Company | Hydraulic disc brake drum-in-hat parking brake assembly |
US5109861A (en) * | 1989-04-28 | 1992-05-05 | Thomas Jefferson University | Intravascular, ultrasonic imaging catheters and methods for making same |
GB2233094B (en) | 1989-05-26 | 1994-02-09 | Circulation Res Ltd | Methods and apparatus for the examination and treatment of internal organs |
JP2789234B2 (en) * | 1989-10-02 | 1998-08-20 | 株式会社日立メディコ | Ultrasound diagnostic equipment |
US5226847A (en) * | 1989-12-15 | 1993-07-13 | General Electric Company | Apparatus and method for acquiring imaging signals with reduced number of interconnect wires |
GB2258364A (en) | 1991-07-30 | 1993-02-03 | Intravascular Res Ltd | Ultrasonic tranducer |
US5744898A (en) * | 1992-05-14 | 1998-04-28 | Duke University | Ultrasound transducer array with transmitter/receiver integrated circuitry |
US5345139A (en) * | 1993-08-27 | 1994-09-06 | Hewlett-Packard Company | Electrostrictive ultrasonic probe having expanded operating temperature range |
GB2315020A (en) * | 1996-07-11 | 1998-01-21 | Intravascular Res Ltd | Ultrasonic visualisation catheters |
US6296619B1 (en) * | 1998-12-30 | 2001-10-02 | Pharmasonics, Inc. | Therapeutic ultrasonic catheter for delivering a uniform energy dose |
US6499348B1 (en) * | 1999-12-03 | 2002-12-31 | Scimed Life Systems, Inc. | Dynamically configurable ultrasound transducer with integral bias regulation and command and control circuitry |
-
2000
- 2000-10-14 GB GB0025250A patent/GB2368123A/en not_active Withdrawn
-
2001
- 2001-10-11 EP EP01974506A patent/EP1324702B1/en not_active Expired - Lifetime
- 2001-10-11 AU AU2001294020A patent/AU2001294020A1/en not_active Abandoned
- 2001-10-11 DE DE60103417T patent/DE60103417T2/en not_active Expired - Lifetime
- 2001-10-11 JP JP2002535554A patent/JP2004511290A/en not_active Withdrawn
- 2001-10-11 US US10/398,967 patent/US8118742B2/en active Active
- 2001-10-11 AT AT01974506T patent/ATE266968T1/en not_active IP Right Cessation
- 2001-10-11 WO PCT/GB2001/004548 patent/WO2002032315A1/en active Application Filing
-
2012
- 2012-02-21 US US13/401,574 patent/US20120232400A1/en not_active Abandoned
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5465725A (en) * | 1993-06-15 | 1995-11-14 | Hewlett Packard Company | Ultrasonic probe |
EP0671221A2 (en) * | 1994-03-11 | 1995-09-13 | Intravascular Research Limited | Ultrasonic transducer array and method of manufacturing the same |
US5947905A (en) * | 1997-10-15 | 1999-09-07 | Advanced Coronary Intervention, Inc. | Ultrasound transducer array probe for intraluminal imaging catheter |
US6605043B1 (en) * | 1998-11-19 | 2003-08-12 | Acuson Corp. | Diagnostic medical ultrasound systems and transducers utilizing micro-mechanical components |
Non-Patent Citations (1)
Title |
---|
Wallace A. Smith; New opportunities in ultrasonic transducers emerging from innovations in piezoelectric materials (Invited Paper). Proc. SPIE 1733, New Developments in Ultrasonic Transducers and Transducer Systems, 3 (November 5, 1992); doi:10.1117/12.130585. * |
Cited By (61)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9867530B2 (en) | 2006-08-14 | 2018-01-16 | Volcano Corporation | Telescopic side port catheter device with imaging system and method for accessing side branch occlusions |
US9596993B2 (en) | 2007-07-12 | 2017-03-21 | Volcano Corporation | Automatic calibration systems and methods of use |
US9622706B2 (en) | 2007-07-12 | 2017-04-18 | Volcano Corporation | Catheter for in vivo imaging |
US10219780B2 (en) | 2007-07-12 | 2019-03-05 | Volcano Corporation | OCT-IVUS catheter for concurrent luminal imaging |
US11350906B2 (en) | 2007-07-12 | 2022-06-07 | Philips Image Guided Therapy Corporation | OCT-IVUS catheter for concurrent luminal imaging |
US11141063B2 (en) | 2010-12-23 | 2021-10-12 | Philips Image Guided Therapy Corporation | Integrated system architectures and methods of use |
US11040140B2 (en) | 2010-12-31 | 2021-06-22 | Philips Image Guided Therapy Corporation | Deep vein thrombosis therapeutic methods |
US9360630B2 (en) | 2011-08-31 | 2016-06-07 | Volcano Corporation | Optical-electrical rotary joint and methods of use |
US20130227826A1 (en) * | 2012-03-05 | 2013-09-05 | Xerox Corporation | Print head transducer dicing directly on diaphragm |
US9139004B2 (en) * | 2012-03-05 | 2015-09-22 | Xerox Corporation | Print head transducer dicing directly on diaphragm |
US20170290562A1 (en) * | 2012-05-11 | 2017-10-12 | Volcano Corporation | Ultrasound catheter for imaging and blood flow measurement |
US10568586B2 (en) | 2012-10-05 | 2020-02-25 | Volcano Corporation | Systems for indicating parameters in an imaging data set and methods of use |
US9307926B2 (en) | 2012-10-05 | 2016-04-12 | Volcano Corporation | Automatic stent detection |
US9478940B2 (en) | 2012-10-05 | 2016-10-25 | Volcano Corporation | Systems and methods for amplifying light |
US11510632B2 (en) | 2012-10-05 | 2022-11-29 | Philips Image Guided Therapy Corporation | Systems for indicating parameters in an imaging data set and methods of use |
US9292918B2 (en) | 2012-10-05 | 2016-03-22 | Volcano Corporation | Methods and systems for transforming luminal images |
US11272845B2 (en) | 2012-10-05 | 2022-03-15 | Philips Image Guided Therapy Corporation | System and method for instant and automatic border detection |
US11864870B2 (en) | 2012-10-05 | 2024-01-09 | Philips Image Guided Therapy Corporation | System and method for instant and automatic border detection |
US9286673B2 (en) | 2012-10-05 | 2016-03-15 | Volcano Corporation | Systems for correcting distortions in a medical image and methods of use thereof |
US9367965B2 (en) | 2012-10-05 | 2016-06-14 | Volcano Corporation | Systems and methods for generating images of tissue |
US11890117B2 (en) | 2012-10-05 | 2024-02-06 | Philips Image Guided Therapy Corporation | Systems for indicating parameters in an imaging data set and methods of use |
US10070827B2 (en) | 2012-10-05 | 2018-09-11 | Volcano Corporation | Automatic image playback |
US9324141B2 (en) | 2012-10-05 | 2016-04-26 | Volcano Corporation | Removal of A-scan streaking artifact |
US9858668B2 (en) | 2012-10-05 | 2018-01-02 | Volcano Corporation | Guidewire artifact removal in images |
US10724082B2 (en) | 2012-10-22 | 2020-07-28 | Bio-Rad Laboratories, Inc. | Methods for analyzing DNA |
US10238367B2 (en) | 2012-12-13 | 2019-03-26 | Volcano Corporation | Devices, systems, and methods for targeted cannulation |
US9709379B2 (en) | 2012-12-20 | 2017-07-18 | Volcano Corporation | Optical coherence tomography system that is reconfigurable between different imaging modes |
US11892289B2 (en) | 2012-12-20 | 2024-02-06 | Philips Image Guided Therapy Corporation | Manual calibration of imaging system |
US10942022B2 (en) | 2012-12-20 | 2021-03-09 | Philips Image Guided Therapy Corporation | Manual calibration of imaging system |
US10939826B2 (en) | 2012-12-20 | 2021-03-09 | Philips Image Guided Therapy Corporation | Aspirating and removing biological material |
US11141131B2 (en) | 2012-12-20 | 2021-10-12 | Philips Image Guided Therapy Corporation | Smooth transition catheters |
US9730613B2 (en) | 2012-12-20 | 2017-08-15 | Volcano Corporation | Locating intravascular images |
US10595820B2 (en) | 2012-12-20 | 2020-03-24 | Philips Image Guided Therapy Corporation | Smooth transition catheters |
US11406498B2 (en) | 2012-12-20 | 2022-08-09 | Philips Image Guided Therapy Corporation | Implant delivery system and implants |
US9486143B2 (en) | 2012-12-21 | 2016-11-08 | Volcano Corporation | Intravascular forward imaging device |
US11786213B2 (en) | 2012-12-21 | 2023-10-17 | Philips Image Guided Therapy Corporation | System and method for multipath processing of image signals |
US10413317B2 (en) | 2012-12-21 | 2019-09-17 | Volcano Corporation | System and method for catheter steering and operation |
US10420530B2 (en) | 2012-12-21 | 2019-09-24 | Volcano Corporation | System and method for multipath processing of image signals |
WO2014099763A1 (en) | 2012-12-21 | 2014-06-26 | Jason Spencer | System and method for graphical processing of medical data |
WO2014099760A1 (en) | 2012-12-21 | 2014-06-26 | Mai Jerome | Ultrasound imaging with variable line density |
US11253225B2 (en) | 2012-12-21 | 2022-02-22 | Philips Image Guided Therapy Corporation | System and method for multipath processing of image signals |
US10332228B2 (en) | 2012-12-21 | 2019-06-25 | Volcano Corporation | System and method for graphical processing of medical data |
US9226711B2 (en) | 2012-12-21 | 2016-01-05 | Volcano Corporation | Laser direct structured catheter connection for intravascular device |
US9612105B2 (en) | 2012-12-21 | 2017-04-04 | Volcano Corporation | Polarization sensitive optical coherence tomography system |
US10191220B2 (en) | 2012-12-21 | 2019-01-29 | Volcano Corporation | Power-efficient optical circuit |
US10166003B2 (en) | 2012-12-21 | 2019-01-01 | Volcano Corporation | Ultrasound imaging with variable line density |
US10993694B2 (en) | 2012-12-21 | 2021-05-04 | Philips Image Guided Therapy Corporation | Rotational ultrasound imaging catheter with extended catheter body telescope |
US9383263B2 (en) | 2012-12-21 | 2016-07-05 | Volcano Corporation | Systems and methods for narrowing a wavelength emission of light |
US10058284B2 (en) | 2012-12-21 | 2018-08-28 | Volcano Corporation | Simultaneous imaging, monitoring, and therapy |
US10027075B2 (en) | 2012-12-21 | 2018-07-17 | Volcano Corporation | Laser direct structured connection for intravascular device |
US9525250B2 (en) | 2012-12-21 | 2016-12-20 | Volcano Corporation | Laser direct structured connection for intravascular device |
US9770172B2 (en) | 2013-03-07 | 2017-09-26 | Volcano Corporation | Multimodal segmentation in intravascular images |
US10226597B2 (en) | 2013-03-07 | 2019-03-12 | Volcano Corporation | Guidewire with centering mechanism |
US10638939B2 (en) | 2013-03-12 | 2020-05-05 | Philips Image Guided Therapy Corporation | Systems and methods for diagnosing coronary microvascular disease |
US11154313B2 (en) | 2013-03-12 | 2021-10-26 | The Volcano Corporation | Vibrating guidewire torquer and methods of use |
US11026591B2 (en) | 2013-03-13 | 2021-06-08 | Philips Image Guided Therapy Corporation | Intravascular pressure sensor calibration |
US9301687B2 (en) | 2013-03-13 | 2016-04-05 | Volcano Corporation | System and method for OCT depth calibration |
US10758207B2 (en) | 2013-03-13 | 2020-09-01 | Philips Image Guided Therapy Corporation | Systems and methods for producing an image from a rotational intravascular ultrasound device |
US10219887B2 (en) | 2013-03-14 | 2019-03-05 | Volcano Corporation | Filters with echogenic characteristics |
US10292677B2 (en) | 2013-03-14 | 2019-05-21 | Volcano Corporation | Endoluminal filter having enhanced echogenic properties |
US10426590B2 (en) | 2013-03-14 | 2019-10-01 | Volcano Corporation | Filters with echogenic characteristics |
Also Published As
Publication number | Publication date |
---|---|
US8118742B2 (en) | 2012-02-21 |
EP1324702B1 (en) | 2004-05-19 |
DE60103417D1 (en) | 2004-06-24 |
EP1324702A1 (en) | 2003-07-09 |
AU2001294020A1 (en) | 2002-04-29 |
DE60103417T2 (en) | 2005-06-09 |
GB0025250D0 (en) | 2000-11-29 |
US20060052707A1 (en) | 2006-03-09 |
ATE266968T1 (en) | 2004-06-15 |
JP2004511290A (en) | 2004-04-15 |
GB2368123A (en) | 2002-04-24 |
WO2002032315A1 (en) | 2002-04-25 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US8118742B2 (en) | Intravascular ultrasonic catheter arrangements | |
EP0671221B1 (en) | Ultrasonic transducer array and method of manufacturing the same | |
US5091893A (en) | Ultrasonic array with a high density of electrical connections | |
US5511296A (en) | Method for making integrated matching layer for ultrasonic transducers | |
JP4807761B2 (en) | Array ultrasonic transducer | |
EP2459322B1 (en) | Ultrasound imaging transducer acoustic stack with integral electrical connections | |
EP1436097B1 (en) | System for attaching an acoustic element to an integrated circuit | |
US5855049A (en) | Method of producing an ultrasound transducer | |
US4385255A (en) | Linear array ultrasonic transducer | |
US11751847B2 (en) | Ultrasound transducer and method for wafer level back face attachment | |
US6669644B2 (en) | Micro-machined ultrasonic transducer (MUT) substrate that limits the lateral propagation of acoustic energy | |
EP0142215A2 (en) | Ultrasound transducer with improved vibrational modes | |
US20090039738A1 (en) | High frequency ultrasound transducers based on ceramic films | |
KR102569596B1 (en) | high frequency ultrasonic transducers | |
US6036647A (en) | PZT off-aperture bonding technique | |
US20130020907A1 (en) | Wire bond free connection of high frequency piezoelectric ultrasound transducer arrays | |
CN110745775A (en) | Process for manufacturing microelectromechanical devices, in particular electroacoustic modules | |
CN112638548B (en) | Non-rectangular transducer arrays and associated devices, systems, and methods | |
US20180269853A1 (en) | Surface acoustic wave wafer level package and method of manufacturing pcb for the same | |
Lay et al. | An easy and inexpensive method for fabricating high frequency annular arrays |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |